State-Space Modelling of Schottky Diode Rectifiers Including Parasitic and Coupling Effects up to the Terahertz Band

A nonlinear state-space model for Schottky diode rectifiers is presented that incorporates junction dynamics, layout parasitic effects, and electromagnetic coupling effects. Unlike prior approaches, the model resolves conduction intervals under harmonic-rich excitation and integrates electromagnetic voltage–current feedback to capture field-induced perturbations at high frequencies. The framework was validated through the design of a 5.8 GHz rectifier, achieving 62% RF–DC efficiency at −10 dBm into a 500 Ω load, with close agreement between the simulation and measurement. The results confirm the model’s predictive accuracy and its utility for high-efficiency rectenna systems in microwave and terahertz applications.